Two factors led to the creation of three new forms of the epact in the Fifteenth and Sixteenth centuries. The first was the increasing error of computistical techniques, which led to the introduction of a new Julian epact around 1478, to be used for practical computations of the phase of the Moon for medical or astrological purposes. With the Gregorian reform of the calendar in 1582, two additional epacts came into use. The first was the Lillian epact, developed by Aloisius Lilius as an element of the ecclesiastical computations using the Gregorian calendar. The Lillian epact included corrections for the motions of the Sun and the Moon that broke the fixed relationship between the epact and the golden number. The second new epact was a simple adjustment of the practical Julian epact to account for the ten-day change produced by the Gregorian Calendar. 
IPv6 ( I nternet P rotocol V ersion 6 ) is also called IPng ( I nternet P rotocol n ext g eneration ) and it is the newest version of the Internet Protocol (IP) reviewed in the IETF standards committees to replace the current version of IPv4 (Internet Protocol Version 4).
IPv6 is the successor to Internet Protocol Version 4 (IPv4). It was designed as an evolutionary upgrade to the Internet Protocol and will, in fact, coexist with the older IPv4 for some time. IPv6 is designed to allow the Internet to grow steadily, both in terms of the number of hosts connected and the total amount of data traffic transmitted.
IPv6 is often referred to as the "next generation" Internet standard and has been under development now since the mid-1990s. IPv6 was born out of concern that the demand for IP addresses would exceed the available supply.